Add three system variables:
1. @DSP: a project property, the date system in current project
0: the current date system, +12 hours off from julian day system
1: julian day
2018: 2018 date system, 0 at 00:00 on Jan 1 2018
2. @DSO: the actual offset for the current date system, in day
And also, when the date system is 2018, Import Wizard support more higher precise date data, for example: When import time data like "2/5/2040 15:59:59.994983" using Import Wizard, can set Custom Date Format as "MM'/'dd'/'yyyy HH':'mm':'ss'.'######" to import.